Correct ballast resistor

You sure you are measuring the correct side, or that it is connected correctly? The dual ballast has a "U" hape opening on one end. This is to "key" the OEM harness connectors sot that it cannot be connected wrong Over the years, that "key" can break, or the connector get damaged, replaced by generic crimp on "flag" push on connectors, etc

Below is a generic, simplified diagram. Notice the "U" at the very bottom of the ballast depiction. Note that as it is viewed in this position, the bottom right terminal goes to the coil. Key switched "run" 12V power comes in, jumpered across both of the top terminals, which are near the enclosed oblong cutout in the ballast.

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